Implementation of Autonomous Directional Drilling and Geosteering to Enhanced Real-Time Decisions Making in MRC Wells, A Case Study from Offshore Abu Dhabi

Abstract Drilling Maximum Reservoir Contacts (MRC) wells is crucial for the development of mature fields. These operations necessitate precise control of the wellbore trajectory to meet objectives during landing, lateral drilling, and geosteering. A potential risk of collision with existing wells or laterals requires comprehensive real-time anti-collision and survey management. Traditionally, skilled directional drillers have relied on their expertise regarding bottomhole assembly (BHA) behavior in specific areas, adjusting drilling parameters and assembly configurations as needed. However, this approach often resulted in deviations from the intended trajectory and performance inconsistencies due to human error. This paper proposes a novel approach by integrating automated drilling and geosteering software to control the downhole BHA, thereby minimizing the need for human intervention. Autonomous drilling requires a software solution that provides real-time, accurate calculations to control the downhole Rotary Steerable System (RSS) and correct the wellpath to stay within the target zone. This system is integrated with automated geosteering software, which reduces the time spent on decision-making—from 15 minutes per decision to under 5 minutes. The integration between the automated drilling and geosteering software also minimizes changes to the RSS settings, resulting in a smoother wellbore, facilitating the use of production BHAs, and reducing Invisible Lost Time (ILT). The case study focuses on an oil producer in a carbonate reservoir, where the well was drilled from a 7" whipstock in the mother hole, landing, and drilling a 6" lateral section. The target zone, a 45-foot-thick carbonate reservoir with water risk, was complicated by geophysical uncertainties and faults. The planned trajectory required a dogleg severity of up to 3.55 degrees for the landing and less than 2 degrees during the lateral section. Offset well analysis emphasized the need for Ultra Deep Resistivity to assess reservoir properties and resolve structural uncertainties. The drilling BHA included a 4 ¾" Intelligent Push-the-bit RSS with Ultra Deep Resistivity and Density Imaging, with the resistivity sensor placed 65 feet behind the bit. Real-time data on near-bit inclination, azimuth, and downhole drilling dynamics (WOB and TOB) were also monitored. The well successfully reached its total depth (TD), drilling and geosteering 7,051 feet with 100% reservoir contact in the target zone. The 6" lateral section was drilled and geosteered using a fully automated downhole drilling platform integrated with geosteering software. This approach allowed for faster real-time decision-making, reducing the number of downlinks required to control the RSS and improving the rate of penetration (ROP). The results from this case study highlight the potential for wider deployment in other fields in Abu Dhabi and lay the groundwork for the future implementation of closed-loop automation solutions.